1. Field of the Invention
This invention relates to an improved anchoring arrangement for use in conjunction with building construction having a masonry wall secured to a steel building column support. More particularly, the invention relates to construction accessory devices, namely, specially-configured column anchors with laser carve-outs that provide high strength pullout resistance when secured to the columns and within the masonry wall bed joints. The invention is applicable to structures having walls constructed from brick, block or stone in combination with building column support.
2. Description of the Prior Art
In the past, investigations relating to the effects of various forces, particularly lateral forces, upon brick veneer masonry construction demonstrated the advantages of having high-strength anchoring components embedded in the bed joints of anchored veneer walls, such as facing brick, block or stone veneer. Anchors are generally placed in one of the following five categories: corrugated; sheet metal; wire; two-piece adjustable; or joint reinforcing. The present invention has a focus on flat-sheet metal material and in particular, single construct column anchors for cavity wall construction having steel column supports.
The use of steel for the construction of building wall supports have become increasingly popular since its inception in the late 1800s. In the 1940s, veneer construction with steel frames was introduced and its popularity has grown steadily since its introduction. This popularity results from the inherent benefits of steel, as opposed to masonry or wood construction. Steel is one of the strongest building frame materials available and is significantly safer, in that it is not susceptible to insect infestation, rotting or destruction from fire. The high strength of a steel structure provides greater resiliency against the effects of aggressive weather. Steel structures are also more cost effective, providing ease of construction and transport and requiring less material than timber or block methods. Steel is also an environmentally-friendly construction material because it is recyclable and results in less raw material waste. Laser cutting of the column anchor is performed by directing the output of a high-power laser, by computer, to melt, burn, or vaporize the desired configuration of the apertures and cut-outs. Examples of lasers used in the laser cutting herein include, but are not limited to, the CO2 laser (and its variants), and the neodymium and neodymium yttrium-aluminium-garnet laser. Laser carving provides the ability to make the detailed carve-outs in the high-strength metals to form the presently presented column anchors. Laser cutting provides advantages over mechanical cutting or plasma cutting because the workholding is easier and there is reduced contamination of the workpiece (there is no cutting edge). Precision is also improved because there is no wear of the cutting edge in the process and the structural integrity of the high-strength metal is uncompromised.
Anchoring systems for wall construction come in varied forms depending on the wall materials and structural use. Ronald P. Hohmann and Hohmann & Barnard, Inc., now a MiTek-Berkshire Hathaway company, have successfully commercialized numerous devices to secure wall structures, providing improvements that include increases in interconnection strength, ease of manufacture and use, and thermal isolation. The present invention is an improvement in interconnection strength and increased pullout prevention.
The high-strength laser configured column anchors of this invention are specially designed to prevent anchor pullout from the masonry wall. The configured anchors are specially-constructed to restrict movement and ensure a high-strength connection and transfer of forces between the steel columns and masonry veneer wall. The column anchor insertion portion, for disposition within the masonry wall, is laser configured to ensure full mortar coverage within the masonry wall bed joint and prevent anchor pullout, while maintaining the requirements for mortar tolerances set forth in the Building Code Requirements for Masonry Structures, Chapter 6, Veneer. The close control of the overall dimensions of the insertion portion permits the mortar of the bed joints to flow through, over and about the anchor to secure against the laser configurations. Because the anchor hereof employs extra strong material and benefits from the laser configuration of the metal, the anchoring system meets the unusual requirements demanded in current building structures.
There have been significant shifts in public sector building specifications which have resulted in architects and architectural engineers requiring larger and larger cavities in the exterior walls of public buildings. These requirements are imposed without corresponding decreases in wind shear and seismic resistance levels or increases in mortar bed joint height. Thus, the wall anchors needed are restricted to occupying the same ⅜-inch bed joint height in the masonry wall. Because of this, the masonry wall material is tied down over a span of two or more times that which had previously been experienced. Exemplary of the public sector building specification is that of the Energy Code Requirement, Boston, Mass. (See Chapter 13 of 780 CMR, Seventh Edition). This Code sets forth insulation R-values well in excess of prior editions and evokes an engineering response opting for thicker insulation and correspondingly larger cavities.
The use of anchors in wall construction have been limited by the mortar layer thicknesses which, in turn are dictated either by the new building specifications or by pre-existing conditions, e.g., matching during renovations or additions the existing mortar layer thickness. While arguments have been made for increasing the number of the fine-wire anchors per unit area of the facing layer, architects and architectural engineers have favored wire formative anchors of sturdier wire. On the other hand, contractors find that heavy wire anchors, with diameters approaching the mortar layer height specification, frequently result in misalignment. Thus, these contractors look towards substituting thinner gage wire formatives which result in easier alignment of courses of block to protect against wythe separation. A balancing of mortar and wall anchor dimensions needs to be struck to ensure wall anchor stability within the masonry wall. The present high strength column anchor greatly assists in maintaining this balance in the mortar joint. The presently presented column anchor provides the required high-strength interconnection within the allowed tolerances.
Besides earthquake protection requiring high-strength anchoring systems, the failure of several high-rise buildings to withstand wind and other lateral forces has resulted in the promulgation of more stringent Uniform Building Code provisions. This high-strength laser configured wall anchor is a partial response thereto. The inventor's related anchoring system products have become widely accepted in the industry.
The following patents are believed to be relevant and are disclosed as being known to the inventor hereof:
U.S. Patent No.InventorIssue Date4,021,990SchwalbergMay 10, 19774,473,984LopezOct. 2, 19844,598,518HohmannJul. 8, 19864,875,319HohmannOct. 24, 19896,298,630VeRost, et al.Oct. 9, 20016,739,105FlemingMay 25, 20047,171,788BronnerFeb. 6, 2007
U.S. Pat. No. 4,021,990—Schwalberg—Issued May 10, 1977 Discloses a dry wall construction system for anchoring a facing veneer to wallboard/metal stud construction with a pronged sheetmetal anchor. The wall tie is embedded in the exterior wythe and is not attached to a straight wire run.
U.S. Pat. No. 4,473,984—Lopez—Issued Oct. 2, 1984 Discloses a curtain-wall masonry anchor system wherein a wall tie is attached to the inner wythe by a self-tapping screw to a metal stud and to the outer wythe by embedment in a corresponding bed joint. The stud is applied through a hole cut into the insulation.
U.S. Pat. No. 4,598,518—Hohmann—Issued Jul. 8, 1986 Discloses a dry wall construction system with wallboard attached to the face of studs which, in turn, are attached to an inner masonry wythe. Insulation is disposed between the webs of adjacent studs.
U.S. Pat. No. 4,875,319—Hohmann—Issued Oct. 24, 1989 Discloses a seismic construction system for anchoring a facing veneer to wallboard/metal stud construction with a pronged sheetmetal anchor. Wall tie is distinguished over that of Schwalberg '990 and is clipped onto a straight wire run.
U.S. Pat. No. 6,298,630—VeRost, et al.—Issued Oct. 9, 2001 Discloses a wall plate for attaching a horizontal or sloping beam to a vertical masonry wall. The wall plate is attached through the use of an anchor affixed to a steel beam. A method of attaching a horizontal or sloping beam to a vertical masonry wall is further disclosed.
U.S. Pat. No. 6,739,105—Fleming—Issued May 25, 2004 Discloses a construction assembly which includes a structure panel, with structural members and integrally molded insulation, a floor support, joists and a horizontal ledge. The assembly further includes cut-out tabs and wall anchors and ties interconnected therewith and secured to the assembly.
U.S. Pat. No. 7,171,788—Bronner—Issued Feb. 6, 2007 Discloses masonry connectors for embedment in masonry wall mortar beds and interconnection with a vertical sliding rail attached to a steel frame. The device, when installed, is designed to be embedded in mortar along the cross ribs of the masonry block and does not require grouting in the cells of the masonry units.
None of the above anchors or anchoring systems provide a laser configured column wall anchor with enhanced interconnection properties and pullout resistance. This invention relates to an improved anchoring arrangement for use in conjunction with building construction having a masonry wall secured to a steel building column support and meets the heretofore unmet need described above.